(1) Field of the Invention
The present invention relates to a foldable communication terminal apparatus, and in particular to a technique for controlling display of content on a display, accompanying opening and closing of the foldable communication terminal.
(2) Description of the Prior Art
In recent years mobile communication devices such as PHS (Personal Handy phone System), PDC (Personal Digital Cellular telecommunication system), and CDMA (Code Division Multiple Access) have become common because of decreases in their size and weight, improvement in their communication quality, and reduction of the price of the devices themselves and of call charges. Currently, such devices are enjoying great popularity amongst young people.
In particular, folding mobile communication devices (hereinafter “folding communication terminal(s)”) which are fashionable and allow for easy operation are popular, resulting in a trend of manufacturers competing against each other to sell folding communication terminals.
A “Selective Radio Call Receiver” disclosed in Japanese Laid-Open Patent Application H6-132876 and a “Portable Telephone Set With Automatically Adjusting Function For Incoming Tone” disclosed in Japanese Laid-Open Patent Application H8-307488 are examples of such conventional folding communication terminals.
These applications disclose techniques for stopping the ringer when there is an incoming-call on detecting that the apparatus has been opened from a folded state.
Furthermore, Japanese Laid-Open Patent Application H11-74953 “Radio Communication Equipment” discloses a folding communication terminal apparatus which has, in addition to a display which is positioned so that it can only be seen when the housing is open and is for displaying information during ordinary use (hereinafter “main display”), an auxiliary display which if for displaying limited information (hereinafter “sub-display”) such as notification of incoming-communication, even when the housing is folded. Here, the maximum number of characters that can be displayed on the sub-display is less than the main display.
However, with such a folding communication terminal, the user must perform cumbersome operations in order to confirm detailed information about who the caller is and so on. The user must first open the housing to have the initial screen displayed on the main display, then locate guidance for confirming the information, and push buttons according to the guidance.